On the surface this is a paper about a TLS implementation, but the really interesting story to me is the attempt to ‘do it right,’ and the techniques and considerations involved in that process. The IT landscape is littered with bug-ridden and vulnerable software – surely we can do better? And if we’re going to make a serious attempt at that, where better than something like a TLS stack – because bugs and vulnerabilities there also expose everything that relies on it – i.e. pretty much the whole of the internet.

The ANSI SQL isolation levels were originally defined in prose, in terms of three specific anomalies that they were designed to prevent. Unsurprisingly, it turns out that those original definitions are somewhat ambiguous and open to both a strict and a broad interpretation. It also turns out that they are not sufficient, since there is one even more basic anomaly not mentioned in the standard that needs to be prevented in order to be able to implement rollback and recovery. Looking even more deeply, the paper uncovers eight different phenomena (anomalies) that can occur, and six different isolation levels.

The main idea of the paper is that the typical failover architecture used when moving from a single datacenter to multiple datacenters doesn’t work well in practice. What does work, where work means using fewer resources while providing high availability and consistency, is a natively multihomed architecture

The job terminations, like the bulk of the media outlet’s work, were first experienced by most Gawker employees in digital, rather than physical space. Deleting the accounts was merely the company’s attempt to assert control of its office space, and Slack’s role in the layoffs simply exemplified where work was actually being done; it also serves as an indicator of, for many employees in the coming years, where it will end.

What happened is when NYSE first allowed [traders] to collocate in the [same building], people started to get into pissing matches over the length of their cables. Just to give you an idea, a foot of cable equates to one nanosecond, which is a billionth of a second. People were getting into pissing matches over a billionth of a second.

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NYSE measured the distance to the furthest cabinet, which is where people put their servers. It was 185 yards. So they gave every [high-frequency trader] a cable of 185 yards.

Then, traders who were previously closer to the [exchange server] asked to move to the farthest end of the building. Why? Because when a cable is coiled up, there's a light dispersion that is slightly greater than when the cable is straight.